I have been using my Olight UC on my desk, connected to one of the ports on my computer.
Though imo it starts out a bit high, slightly over 1C (charging a 650mAh 16340):
it tapers down below 2C within the first 20 minutes, as the charge level rises.
charge finished:
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Here is a test I did of the Olight Universal charger
I connected a 700mAh 16340 battery that was at 3.67v
and the charger started at 610mA initially, so I agree it is a bit high.
After 5 minutes it is down to 540mA and there is no noticeable warmth when I touch the battery
After 10 minutes the battery is still not warm and charge rate is now 480mA
15 minutes into the charging cycle, the rate is now 430mA, and the battery is still not warm.
20 minutes into the charge cycle, the rate is 330mA
25 minutes, charge rate 270mA
30 minutes, charge rate 300mA
35 minutes since the charging started the rate is at 290mA
40 minutes the rate is now 260mA
45 minutes, charge rate 210mA
50 minutes, now 190mA
55 minutes, now 140mA
went to lunch with a friend, was not present for the end of the test
when I got home the charge rate was 0mA, and the charged battery reads 4.1v… all good things
note the green light on the Universal Charger USB plug, confirmed 0mA charge rate
and see the battery voltage at end of charge:
I would say the charger is safe, does not charge too fast, does not heat up the battery, and shuts off completely.
thumbs up!